Harmful effects from local particulate emissions are often underestimated in health impact calculations. Furthermore, local emissions account for the majority of premature deaths in Swedish cities. These are the conclusions presented in a recent PhD thesis from the Department of Environmental Science.
On January 21, David Segersson defended his PhD thesis on the effects of air pollution on health. During his time as a doctoral student at the Department of Environmental Science he studied several Swedish cities and calculated the health effects of local emission on a national scale. He found that local emissions from, for example, traffic and wood burning, caused the majority of premature deaths recorded in Swedish cities and that the impact of local emissions of harmful particles are often underestimated.
“In Sweden, we already use similar methods as those described in my thesis, but in other countries they often follow WHO’s recommendations whereby all small particles are grouped together in the same category, regardless of source or type of particles,” says David Segersson.
Somewhat unexpectedly, he concluded that local emissions account for the majority of premature deaths in Swedish cities, despite the relatively high exposure to particles from distant sources.
“The dissertation provides a scientific reference for national health impact calculations made on behalf of the Swedish Environmental Protection Agency. Examples are also provided of how action strategies can be evaluated and compared in a way that differentiates the exposure to pollutants near the source and that to particles that are transported over long distances. If the difference is not taken into account, then there is a risk that the benefits from reduction measures will be greatly underestimated,” points out Segersson.
David Segersson’s work was part of the research project NordicWelfAir and was conducted mainly in collaboration with the City of Stockholm and Umeå University. He is now employed as a researcher at the Swedish Meteorological Institute (SMHI) focusing on urban air quality and health. This year, he will assist the Swedish Environmental Protection Agency with exposure calculations that will be included in a nationwide evaluation on the health impact of air pollution.